1. Field of the Invention
The present invention relates to interactive presentation systems that use projectors.
2. Description of the Background Art
In recent years, projectors are widely used as apparatuses for presentations. Screens displayed on information terminal apparatuses can be enlarged and projected on image projection areas by simply connecting image output terminals of the information terminal apparatuses to projectors by using, for example, VGA cables or the like. Then, operations such as switching screens and turning a page forward can be performed on the information terminal apparatuses by using operational remote controls. However, recently, there has been a demand for presentation apparatuses allowing more interactive and diverse operations. In systems (e.g., Patent Literature 1) which have been developed in order to respond to such a demand, operation commands are assigned to positions on a menu screen displayed in an image projection area, and a command assigned to an arbitrary position within an area of the menu screen is executed when the position is pointed by using a pointer.
FIG. 18 shows a configuration of a conventional interactive presentation system. With regard to the reference characters, element 25 represents a projector capable of enlarging and projecting an image, element 26 represents an imaging apparatus capable of taking an image of an imaging area, element 27 represents an information terminal apparatus such as a personal computer or the like, and element 28 represents a transmission device such as a pointer or the like. Furthermore, element 29 represents an image projection area for receiving a projection from the projector 25, and element 30 represents an imaging area of the imaging apparatus 26.
The basic principle on how the above described system operates will be briefly described next. First, a pattern image (menu screen) is displayed in the image projection area of the projector. A presenter points to an arbitrary position in the pattern image by using a pointer. Then, an image of the pointer is taken by a recognition camera whose focus has been preset on the position of the image projection area constituting the whole imaging range. Next, the information terminal apparatus analyzes whether or not a specified position is in focus within image data received from the recognition camera, and identifies a position that is determined to be out of focus as positional information. An interactive operation is enabled by executing an operation command that is pre-associated with the positional information.